Right about the time of the 2003 Iraqi invasion, American artillery units began to receive one of the few fuze breakthroughs in over half a century. The M782 MOFA (Multi Option Fuze for Artillery) is a multi-mode fuze. There are four basic basic fuze functions for artillery shells. And never before have all four been found in one fuze. The M782 can be set to explode on contact, or after a short delay once hitting something (if you want do more damage to fortifications or buildings). The other two functions are ToT (time on target) where the shell explodes in the air after a certain number of seconds. Finally, there is Proximity, where a tiny radar set in the fuze detonates when the shell is 20-30 feet from something (usually the ground). The ToT and Proximity setting both produce air-bursts, which do more damage because fewer of the fragments go right into the ground.
MOFA can also be set by machine, which is how fuzes are set if a lot of them have to be set in a short amount of time. MOFA made life a lot easer for artillery crews, and since early 2003, hardly any of the older fuzes are used any more. MOFA comes in two versions, one for 105mm shells, and the other 155mm shells.